• Polymer(Korea)
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• v.35 no.5
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• pp.378-384
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• 2011

Silk fibroin is a biocompatible and slowly biodegradable natural polymer. This natural polymer has excellent mechanical properties, non-toxicity, and non-immunogenic properties and has been demonstrated to support tissue regeneration. Also, gelatin is a natural material derived from collagen by hydrolysis and has an almost identical composition as that of collagen. Silk fibroin/gelatin scaffolds have been fabricated by using the freeze-drying method. To establish the scaffold manufacturing condition for silk fibroin and gelatin, we made scaffolds with various compositions of gelatin, glutaldehyde and silk fibroin. The silk fibroin/gelatin scaffolds were characterized using SEM, DSC, and water absorption ability tests. The cellular proliferation was evaluated by WST assay. These results suggested that a scaffold containing 8% of gelatin, 1% of glutaldehyde and 0.3 g of silk fibroin provided suitable characterstics for cell adhesion and proliferation. In conclusion, the silk fibroin/gelatin scaffold may serve as a potential cell delivery vehicle and a structural basis for tissue engineering.

• YAKHAK HOEJI
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• v.55 no.6
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• pp.478-484
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• 2011

Non-alcoholic fatty liver disease is known to be frequently associated with obesity and type 2 diabetes. We examined the effects of EtOH extracts from Triticum aestivum on lipid accumulation during the differentiation of 3T3-L1 preadipocytes to screening the candidate materials in preventing non-alcoholic fatty liver disease. The lipid level in adipocytes was determined by Oil Red O staining. The treatment of 50% ethanol, but not water and 100% ethanol extracts, from Triticum aestivum at concentration of 0.5 $mg/ml$ inhibited lipid accumulation in 3T3-L1 cells, revealing no cell toxicity. Thus, the fractions of $CH_2Cl_2$, EtOAc and BuOH were separated from 50% EtOH extract to characterize anti-adipogenic effect. The $CH_2Cl_2$ fraction at concentration of $50{\mu}g/ml$ effectively inhibited the lipid accumulation in the adipocytes compared to those of EtOAc and BuOH at concentration of $50{\mu}g/ml$. The intracellular triglyceride accumulation also was significantly reduced by treatment of $CH_2Cl_2$ fraction in concentration-dependent manner. Western blot analysis showed that the $CH_2Cl_2$ fraction attenuated the intracelluar level of fatty acid synthase(FAS) accompanied by attenuated expression of Peroxidase proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) adipogenic transcription factor. These results suggest that $CH_2Cl_2$ fraction from 50% EtOH extract of Triticum aestivum may has the potent anti-adipogenic effects by inhibiting the transactivation of $PPAR{\gamma}$.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.10
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• pp.855-864
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• 2009

The effect of toxicant on the inhibition of nitrification was investigated, using concentrated nitrifying bacteria of both attached and suspended growth. This nitrifying organism was originally obtained from the activated sludge of sewage treatment plant and cultivated for more than three months. The object of this experiment is to determine the effect of the specific surface area and the growth condition of nitrifying bacteria on toxicity of heavy metal. The results of this study were as follows. The specific surface area of both attached and suspended growth of nitrifying organism was proven to be a major factors in determining the inhibition of nitrification of heavy metal such as $Cu^{++}$ion. When the condition of attachment and detachment was compared in an experiment using attached growth nitrifier, the effect on toxicant was 1.12 times less in attached condition than in detached condition for Nitrosomonas, and 1.09 times less for Nitrobacter. In case of suspended growth nitrifier, the effect on toxicant was 1.46 times less in non-ground condition than in ground condition for Nitrosomonas, and 1.35 times less for Nitrobacter. Also, similar results were obtained in a set of experiments, without adding nitrite to the substrate. In an experiment that compared attached condition using attached growth nitrifier with detached condition using attached growth nitrifier, the effect on toxicant was 1.83 times less in attached condition than in detached one for Nitrosomonas, and 1.78 times less for Nitrobacter. In case of suspended growth nitrifier, the effect on toxicant was 1.27 times less in non-ground condition than in ground condition for Nitrosomonas, and 1.32 times less for Nitrobacter.

• Weed & Turfgrass Science
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• v.4 no.2
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• pp.104-110
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• 2015

This study was conducted for 3 years in an apple orchard to investigate the efficacy of the glufosinate-ammonium (GFA) SL for weed control in comparison to non-woven fabric mulch, sod culture and machinery cutting treatments. Glufosinate-ammonium SL 18% was applied with 2 to 3 times, and the extents of injury caused by the different weed control methods were also investigated during the 3 years. The highest level of weed control was obtained by glufosinate-ammonium 3 times spray (98.7%), followed by machinery cutting (95.1%), glufosinate-ammonium 2 times spray (81.5%) and natural sod culture (5.8%). Amounts of fruit production in three times application of glufosinate-ammonium 540 g a.i. $ha^{-1}$, twice application of GFA, machinery cutting, non-woven fabric processing, sod culture and untreated control were 27.2, 26.2, 25.3, 24.1, 20.4 and 13.3 kg, respectively. There was no toxicity symptom of glufosinate-ammonium on the whole tree such as fruit, bud, trunk, branch and flower during the 3 years.

• Radiation Oncology Journal
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• v.36 no.3
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• pp.182-191
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• 2018

Purpose: To investigate the clinical outcome of proton therapy (PT) in patients with chordoma. Materials and Methods: Fifty-eight patients with chordoma treated with PT between June 2007 and December 2015 at the National Cancer Center, Korea, were retrospectively analyzed. The median total dose was 69.6 cobalt gray equivalent (CGE; range, 64.8 to 79.2 CGE). Local progression-free survival (LPFS), distant metastasis-free survival (DMFS), overall survival (OS), and disease-specific survival (DSS) rates were calculated by the Kaplan-Meier method. Results: With the median follow-up of 42.8 months (range, 4 to 174 months), the 5-year LPFS, DMFS, OS, and DSS rates were 87.9%, 86.7%, 88.3%, and 92.9%, respectively. The tumor location was associated with the patterns of failure: the LPFS rates were lower for cervical tumors (57.1%) than for non-cervical tumors (93.1%) (p = 0.02), and the DMFS rates were lower for sacral tumors (53.5%) than for non-sacral tumors (100%) (p = 0.001). The total dose was associated with both the LPFS rate and DMFS rate. The initial tumor size was associated with the DMFS rate, but was not associated with the LPFS rate. Three patients had grade 3 late toxicity with none ≥grade 4. Conclusion: PT is an effective and safe treatment in patients with chordomas. The tumor location was associated with the patterns of failure: local failure was common in cervical tumors, and distant failure was common in sacral tumors. Further refinement of PT, such as the utilization of intensity modulated PT for cervical tumors, is warranted to improve the outcome.

• Polymer(Korea)
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• v.33 no.2
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• pp.111-117
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• 2009

This study aims to verify for humans the suitability of the enzyme-fixed hydrogel used for the patch sensor of the blood sugar testing system without blood sampling, which utilizes reverse iontophoresis. Using acrylate monomers, hydrogel was synthesized to which a certain unit of enzyme is fixed. In order to analyze the material property of the synthesized hydrogel, a structural analysis was performed using FT-IR spectroscopy, while the DSC was used to verify the thermal stability. In addition, with the UV-Vis spectrophotometer, it was verified that the degree of active enzyme is at least 50% greater than the standard product. The SEM was used to verify secure fixation of the enzyme onto the surface. As a result, it was observed that the enzyme is successfully fixed to the surface. Since the hydrogel makes direct contact with a patient's skin, it is essential to evaluate the toxicity when making direct contact with the skin. For that purpose, various sets of tests were undertaken according to the ISO 10993-cytotoxicity, intracutaneous reactivity, skin irritation test and maximization sensitization. Consequently, it was successfully verified that the enzyme-fixed hydrogel have bioavailability.

• Ecology and Resilient Infrastructure
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• v.8 no.3
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• pp.135-142
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• 2021

Biopolymers have been known as eco-friendly soil strengthening materials and studied to apply levees. However, the effect of biopolymer on vegetation is not fully understood. In this study, we analyzed the root growth of Camelina sativa L. (Camelina) when the xanthan gum was amended to soil in Aluminum (Al) stress conditions. Amendment of 0.05% xanthan gum increased root growth of Camelina under Al stress conditions. Under the Al stress condition, expression of aluminum activate malate transporter 1 (ALMT1) gene of Camelina root was induced but showed a lower level of expression in xanthan gum amended soil than non-amended soil. Additionally, the binding capacity of xanthan gum with Al ions in the solution was confirmed. Using morin staining and ICP-OES analysis, the Al content of the roots in the xanthan gum soil was lower than in the non-xanthan gum soil. These results suggest that xanthan gum amended soils may reduce the detrimental effects of Al on the roots and positively affect the growth of plants. Therefore, xanthan gum is not only an eco-friendly construction material but also can protect the roots in the disadvantageous environment of the plant.

• Applied Chemistry for Engineering
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• v.29 no.6
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• pp.690-695
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• 2018

Advanced oxidation processes (AOPs) composed of O3 and UV were applied to degrade penicillin (PEN). The degradation efficiency was evaluated in terms of changes in the absorbance (ABS) and total organic carbon (TOC). The combination of $O_3/H_2O_2/UV$ and $O_3/UV$ showed the best performance for the reduction of ABS (100% for 9 min) and TOC (70% for 60 min) values, although the mineralization was uncompleted under the experimental condition in this study. The change in biotoxicy was monitored with Escherichia coli susceptibility and Vibrio fischeri biofluorescence. The E. coli susceptibility was eliminated completely for 9 min by $O_3/UV$, and the toxicity to V. fischeri biofluorescence was 57% reduced by $O_3/H_2O_2/UV$. For the ultimate treatment of PEN, it is suggested that an AOP using $O_3/UV$ is followed by biological treatment, utilizing the enhanced biodegradability by the AOP. During 30 min of $O_3/UV$ treatment, the $BOD_5/COD$ ratio as an indication of biodegradability showed about 4-fold increment, compared to that of using a non-treated sample. TOC removal rate for AOP-pretreated PEN wastewater increased 55% compared to that of using the non-pretreated one through an aerobic biological treatment by Pseudomonas putida for artificial wastewater containing 20 mg/L of PEN. In conclusion, $O_3/UV$ process is recommended as a pretreatment step prior to an aerobic biological process to improve the ultimate degradation of penicillin.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.89-98
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• 2009

Objectives : The purpose of this study was to evaluate effects of processed sulfur with red ginseng on streptozotocin(STZ) induced diabetic rats for expansion of processed sulfur internal application. Methods : We prepared red ginseng with non processed sulfur extracts(GS), red ginseng with processed sulfur I extracts(GPS I) and red ginseng with processed sulfur II extracts(GPS II). In the present study, we examined about contents of crdue saponin, antioxidant activity, $\alpha$-glucosidase inhibitory activity, and effects of STZ induced diabetic rats. Results : Contents of crude saponin increased by processed sulfur, and GPS II was shown highest contents in crude saponin and sulfur compared with another groups. Electron donating ability of GPS II was shown highest activity compared with GS and GPS I, SOD-like activity showed same tendency as electron donating ability at 1 $mg/m\ell$ concentration. Inhibitory activity of $\alpha$-glucosidase was approximately same level in acarbose and GPS II. Blood glucose level of GPS II group was decreased 18.34% compared with DC(diabetes control) group and maintained stability range in glucose level. but GS and GPS I showed high level compared to GPS II. Serum triglycerides concentration also showed lowest level in GPS II. The activity of ALT, AST and ALP was shown high level in diabetic induced groups, and lowest level in GPS II. Creatinine was shown non-significantly difference in each groups and GPS II was shown lowest level in BUN. Conclusions : These results suggested that processed sulfur with red ginseng have improvement effects on diabetes and internal application of processed sulfur with red ginseng have no specific toxicity in liver and kidney.

• The Korean Journal of Pesticide Science
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• v.20 no.1
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• pp.72-81
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• 2016

Feeding behaviors of the pear psylla, Cacopsylla pyricola, and their changing feeding behaviors were recorded and analyzed with an electrical penetration graph (EPG) analysis against 5 insecticides. And their mortality against insecticides were carried out in the laboratory. General feeding behavior patterns of C. pyricola were changed by insecticide treatments. Especially, the type and frequency of waveforms differently occurred depending on a sort of insecticides treated. Total duration of transition to waveform PE1 and phloem ingestion (waveform PE2) were significantly different between treatment and non-treatment of insecticides. When 5 different insecticides were treated on pear leaves, difference of feeding patterns were recorded. In case of treatment of benfuracarb, total duration of non-probes (waveform Np) was appeared higher than any other insecticide. However, when flonicamid and deltamethrin were treatment, total duration of stylet penetration (waveform PA) and xylem ingestion (waveform PG) were appeared higher than other insecticide, respectively. As results feeding behaviour of C. pyricola after treated insecticides with time-based consumed rate of C. pyricola, the rate of non-probe (waveform Np) was longer than start penetration (waveform PA), penetration and ingestion in parenchyma cells (waveform PC1+PC2), ingestion at phloem (waveform PD+PE1+PE2) and xylem (waveform PG). As result of direct spray treatment to C. pyricola, mortality of C. pyricola against imidacloprid was higher than any other insecticide on 24 hours after treatment. However, all of insecticides showed 100% mortality of after 48 hours. On the other hand, when 5 insecticides sprayed on the pear leaves and then C. pyricola located on the treated leaves, benfuracarb showed the most toxicity against C. pyricola among insecticides. These result was consistent with the EPG results that showed relatively longer total duration time of waveform Np (non-probes) by benfuracarb treatment.